For the past couple months I go to start my car and I have to step on the gas a couple times before it would start. Or I try to start it without pumping the gas and turn the key twice. The second time around it starts up and when it does the rpm gauge starst hopping . I got a 02 sensor code. A MAF code and knock sensor (maybe). I changed the 02 and MAF. Still the same problem. I read the stickes about knock and throtle positions sensors. Which one should I change or is there somehting else to look at? $62 for TPS and $54 for a knock sensor. I don't wanna spend money I don't have to.

 

clean the intake manifold, throttle body and ivac.

 

I did all that first.

 

buy the tps first becuase i dont think a knock would make your car run that bad (if it runs at all) also even though you replaced your maf sensor check the connections and make sure theyre all still intact, also go buy some crc maf sensor cleaner its like 6 bucks at advanced auto and clean the hotwires on your maf(the wires inside the tube)

 

after reading it again it sounds like an air problem not a knock sensor.

 

buy CRC MAF cleaner and clean your MAF. Check for any codes. Is the CEL on? Could be a CPS sensor.